Improvement in the manufacture of white lead



UNITED STATES Armv'r rrron ASA P. MEYLERT, OF NEIV BRITAIN, CONNECTICUT.

IMPROVEMENT IN THE MANUFACTURE OF WHITE LEAD.

Specification forming part of Letters Patent No. 151,497, dated June 2,1874; application filed March 10, 1874.

To all whom it may concern:

Be it known that I, Asa P. MEYLERT, of New Britain, in the county ofHartford and State of Connecticut, have invented certain new and usefulImprovements in the Mannfacture of lVhite Lead, of which the followingis a specification:

By my process carbonic-acid gas is taken from the chimney of an ordinarylimekiln to the corroding-rooms, all as hereinafter described.

Ordinary limekilns are of two kinds, known as perpetual andintermittent. The former is so arranged that fresh fuel and limestonemay be added from time to time and the burnt lime removed withoutputting out the fire, whereby the kiln may be kept in operation anindefinite time. In the intermittent kiln, when the limestone has beenburned, the fire is allowed to die out, and when the kiln has becomesufficiently cooled oif the burnt lime is removed and the kiln rechargedwith a fresh supply of limestone and fuel for another burning.

In case two of this class of kilns are near each other, one may becleaned out and recharged while the other is burnin The time necessaryfor corroding lead is greater than the time required to burn a kiln oflime; th erefore, if the intermittent kiln is employed, two or more arenecessary in order to keep up a continuous supply of carbonic-acid gas.

I place a hood or cap over the top of the chimney of one or morelimekilns, and connect said chimney or chimneys and the corrodin g roomor cham ber of a white-lead works by means of a pipe provided with ablower or pump to draw the gas from the chimney and force it into thecorroding-room. If, however, the corroding-room is located sufficientlyabove the liinekiln, the gas will rise and flow into the corrodingroomswithout the aid of a blower. The pipe or pipes should also be providedwith a damper to regulate the amount of gas flowing into thecorroding-rooms.

The carbonic-acid gas generated from burning limestone, marble, chalk,&c., is so pure that it needs but little if any purification beforeintroducing it into the corroding-room. A small jet of steam let intothe pipe to precipitate particles of lamp-blaek, or other particles thatmay flow from the limekiln, is all the purifying that will ordinarily berequired. Acetic or other acid may be placed or introduced into thecorroding-room in any desired manner, and the corroding room or roomsmay be of any ordinary construction.

The operation is as follows: Metallic lead is placed in thecorroding-room, and limestone or marble is burned in one of the kilns,and the carbonic-acid gas generated in said kiln is taken to thecorroding-room, as before described. hen the limestone in the kiln firstfired is sufficiently burned, or nearly so, fire is started in kilnnumber two, and the carbonicacid gas arising therefrom is taken to thecorroding-room in like manner. The kiln number one is then cleared out,and the lime saved as in the ordinary manufacture of lime, and the kilnrecharged ready to ignite as soon as the kiln number two is exhausted,and so on, thus keeping up a continual supply of earbonicacid gas solong as may be desired; but, as before stated,'if a perpetual kiln isemployed, only one kiln is necessary. After corrosion, the lead istreated in the usual manner.

By thus combining the manufacture of marketable lime and white lead inone and the same process, the cost of the lime is not increased, whilethe cost of producing the white lead is materially decreased.

I claim as my invention- The process of corroding lead herein described,by conveying carbonic-acid gas from one or more limekilns to thecorroding-rooms, all substantially as described.

ASA P. MEYLERT.

W itn esscs JAMES SHEPARD, Fosrnn N. GUNNIsoN.

